The subject matter disclosed herein relates to a sealing structure between a rotating component and a static component and, more particularly, to a compliant plate seal arrangement manufacturing method.
Dynamic sealing between a rotor (e.g., rotating shaft) and a stator (e.g., static shell or casing) is an important concern in turbomachinery. Several methods of sealing have been used. In particular, sealing based on flexible members has been used that include seal members such as compliant plate seals.
Known brush seals include tightly-packed, generally cylindrical bristles that are arranged in a staggered arrangement to reduce leakage. The bristles have a low radial stiffness that allows them to move in the event of a rotor excursion while maintaining a tight clearance during steady state operations. Brush seals, however, are generally effective only below a limited pressure differential across the seal. Because of the generally cylindrical geometry of the bristles, the brush seals tend to have a low stiffness in the axial direction, which limits the maximum operable pressure differential in known brush seals to generally less than 400 psi.
Compliant plate seals have plate-like elements that have a significantly higher axial stiffness for a comparable radial stiffness and therefore such seals have the capability of being used with larger pressure differentials than known brush seals.
Compliant plate seals, often including thin plate like elements assembled together as a pack, are welded to a housing that supports the plates relative to a rotor (e.g., a rotating shaft). One method of joining is by welding. During the welding process, the joined region of the compliant members can shrink which causes distortion and wrinkling of the compliant plate elements, which can affect the radial stiffness of and the force distribution on the compliant plates, which can lead to several problems including increased axial leakage and rotor heating.